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STATE BOARD OF AGRICULTURE. 



flavor than upon the solubility of nitrogenous compounds. This part of 

 the ripening process cannot be included in our discussions, unless we 

 find an accurate method of determining flavoi-s quantitatively. 



It may be said against this discussion of cheese ripening that 

 the factors important for microbial life are not constant, changing from 

 the nearly neutral milk to a salted, pressed, acid curd. This change 

 will naturally affect the development of micro-organisms, but from the 

 time our cui'ves begin to tell the stoi-y of ripening the conditions are 

 nearly constant, excepting the acidity. After the first two days, when 

 100 cc. of the extract require about 140 cc. of n-10 alkali to be neutral- 

 ized, the acidity increases very slowly, amounting to about 190 cc. after 

 two weeks and about 220 cc. after four months; later it decreases slowly. 

 This change in acidity will naturally influence the curve to some extent, 

 but not enough to convert a fermentation curve into an enzymic curve. 



Whether the rii^ening process of the Swiss cheese follows the curves 

 of the Cheddar cheese or niot, I am not able to say, since I have not suc- 

 ceeded in getting sufficient data for an exact curve. Weigmann (in 

 Lafar, Handbuch II, p. 158) quotes from von Freudenreich that the 

 autolysis of fresh Swiss cheese is very insignificant while it is quite 

 vigorous in old cheese. That speaks plainly for a microbial curve. 



A curve similar to the cheddar cheese ripening is found in the in- 

 crease of amid nitrogen in cold storage butter (Rahn, Brown and Smith, 

 Technical Bui. No. 2 of Michigan Exp. Sta. (1909) , p. 29) . The butter kept 



Fig. 10. Amid Nitrogen in Butter. 



